1. Field of the Invention
The present invention relates to orthopedic devices and devices used in the rehabilitation of neurological patients with contracture. In particular, the invention relates to supports and more specifically to an improved foam knee support wherein the knee support is modular, adjustable, and can be used with either one leg to two.
The knee positioning support is comprised of at least one leg-engaging trough portion and can include at least one additional wedge portion which can be attached to either side of the leg-engaging trough portion. The use of two leg-engaging portions attached to opposite sides of a center wedge portion provides a knee positioning support that can accommodate two legs. Because the angle of attachment of the leg-engaging troughs to the wedge portion is adjustable, the two legs can be positioned at a variety of different angles. In addition, the flat bottom surface of the leg-engaging trough has one angled edge which allows the use of the support in either a back-lying or side-lying position. If a side-lying position is desired to be prevented, a wedge portion can be attached to the side of the leg-engaging trough portion that is integrally connected to the angled edge of the bottom of the leg-engaging trough portion. Furthermore, the invention support can be constructed from carvable foam to provide a custom fit, and to accommodate people who do not have symmetrical flexion of the knees.
2. Description of the Related Art
It is often necessary to specifically position the legs of persons with mild to moderate spasticity, arthritis, and contractures, particularly those recovering from strokes, traumatic brain injuries, dementia and other neurological impairments, and persons with lower extremity amputations for extended periods. Specific positioning of the legs helps to flex the hips and knees so as to relieve stress on the lower back and/or maintain the legs in a fixed position. Specific positioning of the knees of such persons also helps prevent further contracture and helps to maintain their current range of leg motion. Patients with severe spasticity, for example patients suffering from cerebral palsy, head trauma, or stroke, often experience a scissors gate; their knees that tend to cross and push into one another. For such patients it is desirable to separate the legs to prevent contracture, and to inhibit the development of further abnormal muscle tone or to position patients that have reduced or minimal muscle strength and mobility.
In addition, these conditions are uncomfortable for the patient, often causing pressure sores due to the bony prominences of the legs in prolonged contact, prolonged skin-on-skin contact, and even prolonged skin on bed-sheet contact due to extensive bed rest.
Certain prior art devices, such as the knee separation cushion described in U.S. Pat. No. 4,889,109 provide a leg cushion with simultaneously supports the legs of a supine wearer in a bent at the knee position, while maintaining a cushion between the knees of said wearer. However, such a prior art device is useful only when both knees are affected. If only one knee is affected, the unaffected leg is still subjected to the fixed positioning. Similarly, U.S. Pat. No. 4,910,818 describes a leg positioning assembly that includes a pillow adapted to separate the knees of a patient and to maintain the knee in flexion. Again, however, this device is useful only for people who wish to maintain a fixed position of both knees relative to each other. It is not particularly helpful for maintaining a single knee in flexion. In addition, both of these prior art devices maintain the hip flexion angle at a fixed position as the position of the knee support device relative to the hip is not adjustable.
U.S. Pat. No. 5,134,739 and U.S. Pat. No. 3,946,451 both provide a device for giving a set position to the lower limbs of persons required to remain in a supine position for an extended period. These devices comprise at least one block offering two side support surfaces for the legs, the vertical plans of the two surfaces converging at a determined angle corresponding to the desired positioning of the two lower limbs. However, unlike the modular knee support of the instant invention, these prior art devices are unsuitable for side-lying persons. The bottom surface of the leg-receiving portion of these prior art devices have two flat edges making it impossible for side-lying persons to comfortably rest their legs and maintain the desired flexion angle position. Furthermore, the side surfaces of the central block of the U.S. Pat. No. 5,134,739 device converges toward the patient and diverges toward the feet further limiting the number of positions the legs and/or hips of the patients can be adjusted.
U.S. Pat. No. 5,289,828 describes a device that allows patients to be in a back-lying or side-lying position. However, this device does not allow the flexion angle of the knee to be variably adjusted. Indeed, the wedge-type device of the 5,289,828 patent does not allow for bending of the knee at all. In addition, only a single leg can be maintained in a specific elevated fixed position by the device of the 5,289,828 patent at one time. Similarly, U.S. Pat. No. 4,392,489 also describes a wedge-like device that does not allow for bending of the knee and requires both legs to be immobilized at once.
None of these prior art knee support devices can provide either a back-lying or side-lying patient the ability to accommodate a variety of flexion angles for either one or both legs while maintaining either one or both knee flexion angles in a fixed, bent position.